The present invention generally relates to an apparatus for automatically applying a liquid mixture for use in providing electric insulation, sealing, bonding and adhering of electronic components, electric components and fine parts, such as bonding of a semiconductor integrated circuit board, epoxy resin molding of a magnetic head and epoxy resin coating on electric components of an automobile. More particularly, this invention relates to a liquid-mixture auto-applying apparatus suitable for mixing a hardener to a main agent of an adhesive, such as an epoxy resin, urethane resin or silicone resin, then injecting and applying the liquid mixture onto the works.
Conventional apparatuses for applying a mixture of two liquids comprise pallets each having work-mounting portions of a circular hole arranged in rows and columns to hold works, and dispensers for injecting a liquid mixture of an adhesive onto the works mounted on the pallets. The prior art apparatuses are classified into a pallet moving type which moves pallets in the X and Y directions (row and column directions) to position specific works mounted on a pallet at where the dispensers are located, and a dispenser moving type which moves dispensers in the X and Y directions above specific works, with the pallets fixed. In either type of apparatus, the dispensers are designed to be vertically movable to inject an adhesive liquid mixture into works.
These prior art apparatuses, however, have the following shortcomings.
First, the former pallet moving type requires an X-Y table for aligning the pallets. This X-Y table should be able to align the pallets at very high precision, which inevitably increases the manufacturing cost of the apparatus. In addition, since the individual works arranged in rows and columns on a pallet are moved in the X and Y directions to a predetermined injecting position, the moving time becomes long and the productivity is impaired.
In the latter dispenser moving type, it is difficult to provide a plurality of dispensers. This design restriction does not permit the use of different dispensers for different types of works. In addition, it requires time to move the dispensers in the X and Y directions to the desired position, thus making it difficult to improve the productivity. Further, movement of the dispensers inevitably requires very large space, which enlarges the apparatus.